The mission of the Mouse Pathology Core (the Core) is to provide histologic and hematopoietic research support services to UCSF Helen Diller Family Comprehensive Cancer Center (Center) investigators studying the pathogenesis and treatment of organ and hematologic malignancies in mouse models of human cancer. This facility provides services for members of many of the Center's programs. Histology services performed by the manager and staff include processing, embedding, and histologic sectioning of murine tissues in paraffin and frozen blocks (with re-embedding of tissue as necessary); routine histochemical staining (hematoxylin and eosin); and other special histochemical stains. In addition to providing both training on and access to the equipment utilized for pathologic analysis of murine tissues, the Core also conducts a mouse pathology workshop that provides training in necropsy, dissection, tissue trimming, and sectioning techniques. Furthermore, the Core provides expertise in murine hematology. Complete blood counts are provided for investigators, including preparation of blood smears for analysis of white blood cell, red blood cell, and platelet morphology. Another service provided by the Core is access to outside veterinary laboratory testing (e.g., serum chemistry assays). The Core also facilitates pathologic consultation for researchers provided by the Co-Directors, Drs. Coussens and Kogan. Offering consultation with the Co- Directors makes available the same expertise an in-house murine pathologist would provide, including aid in planning experiments, and expertise in data analysis at a greatly reduced cost to the organization. The Core was used by laboratory personnel representing approximately 50 different investigators at the Center, providing a total of 8533 units of service during the most recent 12 month period (January 2010 through December 2010). Investigators in many of the Center programs have relied upon the Core not only for direct services, but also for training of their personnel. Demonstration of the utility and expertise of the Core is evident by extensive publications reflecting use of mouse models of human cancer by investigators that utilize this service.